Diaz was one of 18 fighters on the card tested for performance-enhancing drugs and drugs of abuse. The remaining tests received to date have thus far all been negative.

Diaz will ultimately have to appear before the NSAC to address the failed screen. Barring a successful appeal, the offense will serve as Diaz’s second infraction under the commission’s watch. Diaz also tested positive for marijuana following a 2007 win over Takanori Gomi at PRIDE 33. Diaz was suspended for six months for that offense, and the result of the bout was changed to a no-contest.

This past Saturday at UFC 143, Condit earned a unanimous decision over Diaz to become the UFC interim welterweight champion and set a fight with undisputed champ Georges St-Pierre sometime this year. The pay-per-view event took place this past Saturday at the Mandalay Bay Events Center in Las Vegas.

Diaz said he would retire shortly after the decision was handed down. UFC president Dana White then said he would understand if Diaz wanted to retire but also entertained the possibility of a rematch with Condit as St-Pierre healed from the torn ACL that scratched his scheduled meeting with Diaz and this past Saturday’s event.

However, the potential rematch was quickly nixed by Diaz’s camp, who declined to speculate as to the reason.

Diaz and his camp have yet to comment on the test result.

For complete coverage of UFC 143, stay tuned to the UFC Events section of the site.
(Pictured: Nick Diaz)

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